<!DOCTYPE html>
<html>
    <head>
        <script src="vue.js"></script>
    </head>
    <body>
        <div id="app">
            <div v-if="isShow" ref="self">测试div</div>
            <button @click="isShow=!isShow">更新</button>
        </div>
        <script>
            var vm = new Vue({
                el:'#app',
                data:{
                    isShow:false
                },
                beforeUpdate(){
                    console.log('更新之前');
                    console.log(this.$refs.self);
                },
                updated(){
                    console.log('更新之后');
                    console.log(this.$refs.self);
                }
            });
        </script>
    </body>
</html>